Business acquisition estimated fair value assets of free shares.

No definition available.

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- Definition

Business acquisition estimated fair value liabilities of free shares.

+ References

No definition available.

+ Details

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- Definition

Business acquisition, number of free shares held by the holders.

+ References

No definition available.

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- Definition

Business acquisition, number of shares acquired.

+ References

No definition available.

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- Definition

Business acquisition, percentage of equity interests agreed to acquire.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

+ Details

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
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-Name Accounting Standards Codification
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-Topic 350
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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ACQUISITION OF SANGAMO THERAPEUTICS FRANCE S.A.S. - Additional Information (Detail) - USD ($)		2 Months Ended	3 Months Ended			12 Months Ended
	Oct. 01, 2018	Nov. 23, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Jul. 20, 2018
Business Acquisition [Line Items]
Goodwill impairments			$ 0	$ 0
Sangamo France \| Share Purchase Agreement and Tender Offer Agreement
Business Acquisition [Line Items]
Noncontrolling interest ownership percentage			98.70%
Sangamo France
Business Acquisition [Line Items]
Number of ordinary shares acquired (in shares)	13,519,036	11,528,635
Business acquisition, percentage of voting interests acquired							98.20%
Business acquisition, share price (in dollars per share)	$ 2.99
Sangamo France \| Share Purchase Agreement and Tender Offer Agreement
Business Acquisition [Line Items]
Percentage of equity interests agreed to acquire								100.00%
Number of ordinary shares acquired (in shares)					25,047,671	111,000
Number of free shares held by the holders (in shares)								477,000
Estimated fair value liability of free shares						$ 200,000
Estimated fair value asset of free shares			$ 200,000
Sangamo France \| Share Purchase Agreement and Tender Offer Agreement \| Option Pricing Method
Business Acquisition [Line Items]
Estimated fair value liability of free shares	$ 200,000